From: Stevan Little Date: Sun, 7 May 2006 01:54:33 +0000 (+0000) Subject: move-delegation-to-attr X-Git-Tag: 0_09_03~37 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=452bac1b88c2bc806fbe285146d050c73e2119b7;p=gitmo%2FMoose.git move-delegation-to-attr --- diff --git a/TODO b/TODO index 98fd5f6..c03ea5f 100644 --- a/TODO +++ b/TODO @@ -2,8 +2,6 @@ TODO ------------------------------------------------------------------------------- -- make way to iterate over all Moose classes - - roles Need to figure out the details of composite roles diff --git a/lib/Moose.pm b/lib/Moose.pm index 9b31e5c..33fd12a 100644 --- a/lib/Moose.pm +++ b/lib/Moose.pm @@ -117,7 +117,7 @@ use Moose::Util::TypeConstraints; has => sub { my $class = $CALLER; return subname 'Moose::has' => sub { - my ($name, %options) = @_; + my ($name, %options) = @_; my $meta = $class->meta; if ($name =~ /^\+(.*)/) { my $inherited_attr = $meta->find_attribute_by_name($1); @@ -188,12 +188,7 @@ use Moose::Util::TypeConstraints; return \&Scalar::Util::blessed; }, all_methods => sub { - subname 'Moose::all_methods' => sub () { - sub { - my ($class, $delegate_class) = @_; - $delegate_class->compute_all_applicable_methods(); - } - } + subname 'Moose::all_methods' => sub () { qr/.*/ } } ); diff --git a/lib/Moose/Meta/Attribute.pm b/lib/Moose/Meta/Attribute.pm index 505c0f7..14036a1 100644 --- a/lib/Moose/Meta/Attribute.pm +++ b/lib/Moose/Meta/Attribute.pm @@ -13,6 +13,22 @@ use Moose::Util::TypeConstraints (); use base 'Class::MOP::Attribute'; +# options which are not directly used +# but we store them for metadata purposes +__PACKAGE__->meta->add_attribute('isa' => ( + reader => 'isa_metadata', + predicate => 'has_isa_metadata', +)); +__PACKAGE__->meta->add_attribute('does' => ( + reader => 'does_metadata', + predicate => 'has_does_metadata', +)); +__PACKAGE__->meta->add_attribute('is' => ( + reader => 'is_metadata', + predicate => 'has_is_metadata', +)); + +# these are actual options for the attrs __PACKAGE__->meta->add_attribute('required' => (reader => 'is_required' )); __PACKAGE__->meta->add_attribute('lazy' => (reader => 'is_lazy' )); __PACKAGE__->meta->add_attribute('coerce' => (reader => 'should_coerce' )); @@ -26,11 +42,16 @@ __PACKAGE__->meta->add_attribute('trigger' => ( reader => 'trigger', predicate => 'has_trigger', )); +__PACKAGE__->meta->add_attribute('handles' => ( + reader => 'handles', + predicate => 'has_handles', +)); sub new { my ($class, $name, %options) = @_; $class->_process_options($name, \%options); - $class->SUPER::new($name, %options); + my $self = $class->SUPER::new($name, %options); + return $self; } sub clone_and_inherit_options { @@ -68,6 +89,7 @@ sub clone_and_inherit_options { sub _process_options { my ($class, $name, $options) = @_; + if (exists $options->{is}) { if ($options->{is} eq 'ro') { $options->{reader} = $name; @@ -75,13 +97,16 @@ sub _process_options { || confess "Cannot have a trigger on a read-only attribute"; } elsif ($options->{is} eq 'rw') { - $options->{accessor} = $name; - ((reftype($options->{trigger}) || '') eq 'CODE') - || confess "A trigger must be a CODE reference" - if exists $options->{trigger}; + $options->{accessor} = $name; + } + else { + confess "I do not understand this option (is => " . $options->{is} . ")" } } + # process and check trigger here ... + + if (exists $options->{isa}) { if (exists $options->{does}) { @@ -334,6 +359,112 @@ sub generate_reader_method { return $sub; } +sub install_accessors { + my $self = shift; + $self->SUPER::install_accessors(@_); + + if ($self->has_handles) { + + # NOTE: + # Here we canonicalize the 'handles' option + # this will sort out any details and always + # return an hash of methods which we want + # to delagate to, see that method for details + my %handles = $self->_canonicalize_handles(); + + # find the name of the accessor for this attribute + my $accessor_name = $self->reader || $self->accessor; + (defined $accessor_name) + || confess "You cannot install delegation without a reader or accessor for the attribute"; + + # make sure we handle HASH accessors correctly + ($accessor_name) = keys %{$accessor_name} + if ref($accessor_name) eq 'HASH'; + + # install the delegation ... + my $associated_class = $self->associated_class; + foreach my $handle (keys %handles) { + my $method_to_call = $handles{$handle}; + + (!$associated_class->has_method($handle)) + || confess "You cannot overwrite a locally defined method ($handle) with a delegation"; + + if ((reftype($method_to_call) || '') eq 'CODE') { + $associated_class->add_method($handle => $method_to_call); + } + else { + $associated_class->add_method($handle => sub { + ((shift)->$accessor_name())->$method_to_call(@_); + }); + } + } + } + + return; +} + +sub _canonicalize_handles { + my $self = shift; + my $handles = $self->handles; + if (ref($handles) eq 'HASH') { + return %{$handles}; + } + elsif (ref($handles) eq 'ARRAY') { + return map { $_ => $_ } @{$handles}; + } + elsif (ref($handles) eq 'Regexp') { + ($self->has_type_constraint) + || confess "Cannot delegate methods based on a RegExpr without a type constraint (isa)"; + return map { ($_ => $_) } + grep { $handles } $self->_get_delegate_method_list; + } + elsif (ref($handles) eq 'CODE') { + return $handles->($self, $self->_find_delegate_metaclass); + } + else { + confess "Unable to canonicalize the 'handles' option with $handles"; + } +} + +sub _find_delegate_metaclass { + my $self = shift; + if ($self->has_isa_metadata) { + my $class = $self->isa_metadata; + # if the class does have + # a meta method, use it + return $class->meta if $class->can('meta'); + # otherwise we might be + # dealing with a non-Moose + # class, and need to make + # our own metaclass + return Moose::Meta::Class->initialize($class); + } + elsif ($self->has_does_metadata) { + # our role will always have + # a meta method + return $self->does_metadata->meta; + } + else { + confess "Cannot find delegate metaclass for attribute " . $self->name; + } +} + +sub _get_delegate_method_list { + my $self = shift; + my $meta = $self->_find_delegate_metaclass; + if ($meta->isa('Class::MOP::Class')) { + return map { $_->{name} } + grep { $_->{class} ne 'Moose::Object' } + $meta->compute_all_applicable_methods; + } + elsif ($meta->isa('Moose::Meta::Role')) { + return $meta->get_method_list; + } + else { + confess "Unable to recognize the delegate metaclass '$meta'"; + } +} + 1; __END__ @@ -376,6 +507,8 @@ will behave just as L does. =item B +=item B + =back =head2 Additional Moose features @@ -395,6 +528,14 @@ A read-only accessor for this meta-attribute's type constraint. For more information on what you can do with this, see the documentation for L. +=item B + +Returns true if this meta-attribute performs delegation. + +=item B + +This returns the value which was passed into the handles option. + =item B Returns true if this meta-attribute produces a weak reference. diff --git a/lib/Moose/Meta/Class.pm b/lib/Moose/Meta/Class.pm index 5bf56a4..5b0a8e5 100644 --- a/lib/Moose/Meta/Class.pm +++ b/lib/Moose/Meta/Class.pm @@ -83,121 +83,6 @@ sub has_method { return $self->SUPER::has_method($method_name); } -sub add_attribute { - my ($self, $name, %params) = @_; - - my @delegations; - if ( my $delegation = delete $params{handles} ) { - my @method_names_or_hashes = $self->compute_delegation( $name, $delegation, \%params ); - @delegations = $self->get_delegatable_methods( @method_names_or_hashes ); - } - - my $ret = $self->SUPER::add_attribute( $name, %params ); - - if ( @delegations ) { - my $attr = $self->get_attribute( $name ); - $self->generate_delgate_method( $attr, $_ ) for $self->filter_delegations( $attr, @delegations ); - } - - return $ret; -} - -sub filter_delegations { - my ( $self, $attr, @delegations ) = @_; - grep { - my $new_name = $_->{new_name} || $_->{name}; - no warnings "uninitialized"; - $_->{no_filter} or ( - !$self->name->can( $new_name ) and - $attr->accessor ne $new_name and - $attr->reader ne $new_name and - $attr->writer ne $new_name - ); - } @delegations; -} - -sub generate_delgate_method { - my ( $self, $attr, $method ) = @_; - - # FIXME like generated accessors these methods must be regenerated - # FIXME the reader may not work for subclasses with weird instances - - my $make = $method->{generator} || sub { - my ( $self, $attr, $method ) = @_; - - my $method_name = $method->{name}; - my $reader = $attr->generate_reader_method(); - - return sub { - if ( Scalar::Util::blessed( my $delegate = shift->$reader ) ) { - return $delegate->$method_name( @_ ); - } - return; - }; - }; - - my $new_name = $method->{new_name} || $method->{name}; - $self->add_method( $new_name, $make->( $self, $attr, $method ) ); -} - -sub compute_delegation { - my ( $self, $attr_name, $delegation, $params ) = @_; - - - # either it's a concrete list of method names - return $delegation unless ref $delegation; # single method name - return @$delegation if reftype($delegation) eq "ARRAY"; - - # or it's a generative api - my $delegator_meta = $self->_guess_attr_class_or_role( $attr_name, $params ); - $self->generate_delegation_list( $delegation, $delegator_meta ); -} - -sub get_delegatable_methods { - my ( $self, @names_or_hashes ) = @_; - map { ref($_) ? $_ : { name => $_ } } @names_or_hashes; -} - -sub generate_delegation_list { - my ( $self, $delegation, $delegator_meta ) = @_; - - if ( reftype($delegation) eq "CODE" ) { - return $delegation->( $self, $delegator_meta ); - } elsif ( blessed($delegation) eq "Regexp" ) { - confess "For regular expression support the delegator class/role must use a Class::MOP::Class metaclass" - unless $delegator_meta->isa( "Class::MOP::Class" ); - return grep { $_->{name} =~ /$delegation/ } $delegator_meta->compute_all_applicable_methods(); - } else { - confess "The 'handles' specification '$delegation' is not supported"; - } -} - -sub _guess_attr_class_or_role { - my ( $self, $attr, $params ) = @_; - - my ( $isa, $does ) = @{ $params }{qw/isa does/}; - - confess "Generative delegations must explicitly specify a class or a role for the attribute's type" - unless $isa || $does; - - for (grep { blessed($_) } $isa, $does) { - confess "You must use classes/roles, not type constraints to use delegation ($_)" - unless $_->isa( "Moose::Meta::Class" ); - } - - confess "Cannot have an isa option and a does option if the isa does not do the does" - if $isa and $does and $isa->can("does") and !$isa->does( $does ); - - # if it's a class/role name make it into a meta object - for ($isa, $does) { - $_ = $_->meta if defined and !ref and $_->can("meta"); - } - - $isa = Class::MOP::Class->initialize($isa) if $isa and !ref($isa); - - return $isa || $does; -} - sub add_override_method_modifier { my ($self, $name, $method, $_super_package) = @_; # need this for roles ... diff --git a/t/039_attribute_delegation.t b/t/039_attribute_delegation.t new file mode 100644 index 0000000..cd95613 --- /dev/null +++ b/t/039_attribute_delegation.t @@ -0,0 +1,194 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +use Test::More tests => 46; +use Test::Exception; + +BEGIN { + use_ok('Moose'); +} + +# the canonical form of of the 'handles' +# option is the hash ref mapping a +# method name to the delegated method name + +{ + package Foo; + use strict; + use warnings; + use Moose; + + has 'bar' => (is => 'rw', default => 10); + + package Bar; + use strict; + use warnings; + use Moose; + + has 'foo' => ( + is => 'rw', + default => sub { Foo->new }, + handles => { 'foo_bar' => 'bar' } + ); +} + +my $bar = Bar->new; +isa_ok($bar, 'Bar'); + +ok($bar->foo, '... we have something in bar->foo'); +isa_ok($bar->foo, 'Foo'); + +is($bar->foo->bar, 10, '... bar->foo->bar returned the right default'); + +can_ok($bar, 'foo_bar'); +is($bar->foo_bar, 10, '... bar->foo_bar delegated correctly'); + +my $foo = Foo->new(bar => 25); +isa_ok($foo, 'Foo'); + +is($foo->bar, 25, '... got the right foo->bar'); + +lives_ok { + $bar->foo($foo); +} '... assigned the new Foo to Bar->foo'; + +is($bar->foo, $foo, '... assigned bar->foo with the new Foo'); + +is($bar->foo->bar, 25, '... bar->foo->bar returned the right result'); +is($bar->foo_bar, 25, '... and bar->foo_bar delegated correctly again'); + +# we also support an array based format +# which assumes that the name is the same +# on either end + +{ + package Engine; + use strict; + use warnings; + use Moose; + + sub go { 'Engine::go' } + sub stop { 'Engine::stop' } + + package Car; + use strict; + use warnings; + use Moose; + + has 'engine' => ( + is => 'rw', + default => sub { Engine->new }, + handles => [ 'go', 'stop' ] + ); +} + +my $car = Car->new; +isa_ok($car, 'Car'); + +isa_ok($car->engine, 'Engine'); +can_ok($car->engine, 'go'); +can_ok($car->engine, 'stop'); + +is($car->engine->go, 'Engine::go', '... got the right value from ->engine->go'); +is($car->engine->stop, 'Engine::stop', '... got the right value from ->engine->stop'); + +can_ok($car, 'go'); +can_ok($car, 'stop'); + +is($car->go, 'Engine::go', '... got the right value from ->go'); +is($car->stop, 'Engine::stop', '... got the right value from ->stop'); + +# and we support regexp delegation + +{ + package Baz; + use strict; + use warnings; + use Moose; + + sub foo { 'Baz::foo' } + sub bar { 'Baz::bar' } + sub boo { 'Baz::boo' } + + package Baz::Proxy1; + use strict; + use warnings; + use Moose; + + has 'baz' => ( + is => 'ro', + isa => 'Baz', + default => sub { Baz->new }, + handles => qr/.*/ + ); + + package Baz::Proxy2; + use strict; + use warnings; + use Moose; + + has 'baz' => ( + is => 'ro', + isa => 'Baz', + default => sub { Baz->new }, + handles => qr/.oo/ + ); + + package Baz::Proxy3; + use strict; + use warnings; + use Moose; + + has 'baz' => ( + is => 'ro', + isa => 'Baz', + default => sub { Baz->new }, + handles => qr/b.*/ + ); +} + +{ + my $baz_proxy = Baz::Proxy1->new; + isa_ok($baz_proxy, 'Baz::Proxy1'); + + can_ok($baz_proxy, 'baz'); + isa_ok($baz_proxy->baz, 'Baz'); + + can_ok($baz_proxy, 'foo'); + can_ok($baz_proxy, 'bar'); + can_ok($baz_proxy, 'boo'); + + is($baz_proxy->foo, 'Baz::foo', '... got the right proxied return value'); + is($baz_proxy->bar, 'Baz::bar', '... got the right proxied return value'); + is($baz_proxy->boo, 'Baz::boo', '... got the right proxied return value'); +} +{ + my $baz_proxy = Baz::Proxy2->new; + isa_ok($baz_proxy, 'Baz::Proxy2'); + + can_ok($baz_proxy, 'baz'); + isa_ok($baz_proxy->baz, 'Baz'); + + can_ok($baz_proxy, 'foo'); + can_ok($baz_proxy, 'boo'); + + is($baz_proxy->foo, 'Baz::foo', '... got the right proxied return value'); + is($baz_proxy->boo, 'Baz::boo', '... got the right proxied return value'); +} +{ + my $baz_proxy = Baz::Proxy3->new; + isa_ok($baz_proxy, 'Baz::Proxy3'); + + can_ok($baz_proxy, 'baz'); + isa_ok($baz_proxy->baz, 'Baz'); + + can_ok($baz_proxy, 'bar'); + can_ok($baz_proxy, 'boo'); + + is($baz_proxy->bar, 'Baz::bar', '... got the right proxied return value'); + is($baz_proxy->boo, 'Baz::boo', '... got the right proxied return value'); +} + + diff --git a/t/070_delegation.t b/t/070_delegation.t index 27adf0a..29a5c9d 100644 --- a/t/070_delegation.t +++ b/t/070_delegation.t @@ -85,6 +85,7 @@ use Test::Exception; ::lives_ok { has child_b => ( + is => 'ro', default => sub { ChildB->new }, handles => [qw/child_b_method_1/], ); @@ -126,7 +127,7 @@ use Test::Exception; isa => "ChildE", is => "ro", default => sub { ChildE->new }, - handles => "child_e_method_2", + handles => ["child_e_method_2"], ); } "can delegate to non moose class using explicit method list"; @@ -138,6 +139,7 @@ use Test::Exception; default => sub { ChildF->new }, handles => sub { $delegate_class = $_[1]->name; + return; }, ); } "subrefs on non moose class give no meta"; @@ -151,7 +153,7 @@ use Test::Exception; isa_ok( my $p = Parent->new, "Parent" ); isa_ok( $p->child_a, "ChildA" ); -ok( !$p->can("child_b"), "no child b accessor" ); +isa_ok( $p->child_b, "ChildB" ); isa_ok( $p->child_c, "ChildC" ); isa_ok( $p->child_d, "ChildD" ); isa_ok( $p->child_e, "ChildE" );